Flap-lifting mechanism



March 22, 1960 P. s. MAGNA FLAP-LIFTING MECHANISM 2 SheetsSheet 1 FiledAug. 22, 1958 INVENTOR. PETER a. M46444 BY w ZW v LN! (Ii a March 22,1960 P. S.-MAGNA' v FLAP-LIFTING' MECHANISM 2 Sheets-Sheet 2 Filed Aug.22, 1958 INVENTOR. PETER .s. 4146M Mfi M ATTORNEY FLAP-LIFTING MECHANISMPeter S. Magna, Pittsburg, Calif. Application August 22, 1958, SerialNo. 756,707 6 Claims. (Cl. 53-374) This invention relates to a mechanismfor lifting front and back cover flaps of cartons or boxes to facilitatehandling them in a conventional sealing apparatus.

Immediately after a carton is filled with articles, such as nails, itsfour cover flaps commonly project at downward angles from thehorizontal. A conventional sealing apparatus includes a slider bed, achain and bar arrangement for pushing cartons along the bed, and meansassociated with the bed for closing the cover flaps. The

latter means cannot close the two flaps which fold along linestransverse to the direction of travel (i.e.fron t and back flaps)preliminary to sealing, unless these flaps project at upward angles. Thesealing apparatus has been equipped with satisfactory means for liftingand closing the two fiaps which fold along lines parallel to thedirection of travel (i.e. side flaps), but when transversely foldingflaps project downwardly, it has been necessary heretofore to lift themmanually before the closing and holding means can act.

An object of the present invention is to provide a mechanism adapted tobe installed on a conventional carton sealing apparatus forautomatically lifting the transversely folding flaps to positions Whereconventional elements of the apparatus can close them.

A further object is to provide a simple mechanism which acts on eachcarton of a series moving therepast to lift the transversely foldingflaps from downwardly projecting angles to upwardly projecting angles,thereby enabling other mechanism to engage and close these flaps.

In accomplishing these and other objects of the invention, I haveprovided improved details of structure, a preferred form of which isshown in the accompanying drawings, in which:

Figure 1 is a diagrammatic side elevational view of a portion of asealing apparatus equipped with my flaplifting mechanism;

Figure 2 is a side elevational view of the lifting means for a frontflap showing the parts in the position they occupy before engagement bya carton;

Figure 3 is a view similar to Figure 2, but showing the parts in theposition they occupy after fully lifting a front flap;

Figure 4 is a top plan view of the lifting means for a back flap showingthe parts in the position they occupy before engagement by a carton; and

Figure 5 is a view similar to Figure 4, but showing the parts in theposition they occupy while a carton is passing.

Figure 1 shows a portion of a conventional cartonsealing apparatus whichincludes a slider bed 10, a drive sprocket 11 journaled at the exit endof the bed, a take-up sprocket 1'2 journaled at the entry end, and anendless chain 13 running over said sprockets alongside the bed. Asimilarly arranged chain and sprockets are situated on the other side ofthe bed. A plurality of spaced apart carton-pushing bars 14 extendbetween the two chains where they can engage the back walls of carton CC C C and C supported on the bed. The drive sprocket 11 is drivencontinuously by any suitable mechanism 15,

whereby the bars continuously push the cartons along the bed. Eachcarton has a transversely folding front cover. 1 flap 16, a transverselyfolding back cover flap 17, and

parallel-folding side cover flaps 18, all of which normally project atdownward angles from the horizontal, as shown on carton C The apparatusalso includes a finger 19 pivoted on a horizontal axis above bed 10 fordepressing the back flaps 17 and a plate 20 fixed above the exit'portion of the bed for closing andlholding both of the transverselyfolding flaps, as shown on carton C Conventional means, not shown,automatically lowers finger 19 as each carton passes beneath fordepressing the back; flap to a position where plate 20 can hold itclosed. Thej.

apparatus also includes means for closing the parallelfolding side flaps18 and for sealing the cartons, but

'since the present'invention does not involve these parts,

they are not shown. a P

It is apparent from Figure 1 that neither finger 19 nor plate 29 canproperly engage the transversely folding flaps 16 and 17 unless they areprojecting upwardly from the horizontal. If these flaps were to remainin 'the positions shown on carton C they would merely pass under thefinger and plate without closing. In accordance with my invention, thesealing apparatus is equipped with a flap-lifting mechanism whichincludes cooperating means 25 and 26 for automatically lifting thetransversely folding front and back flaps 16 and 17 respectively topositions where the finger and plate can engage them.

The lifting means 25 for the front fiap 16 is located ahead of fingers19 and comprises upright plates 27 fixed with respect to opposite sidesof the slider bed 10 outside chains 13. The two plates 27 arehorizontally aligned and are alike except of opposite hand. Eachcontains.

a slot 28 which slopes upwardly toward the exit end of the bed. A rod 29is slidably supported in'the two slots 28 and extends across the bed inspaced relation there above. Normally the rod gravitates to the lowerends of the slots where it is lower than the bottom edge of a downwardlyprojecting front flap 16, as shown in Figure 2. As the front wall of themoving carton engages the rod, it pushes the rod up the slope of slots28, as shown on carton C in Figure l. The rod thus moves upward-. lyunder the front flap 16 and lifts this flap about its adjacent the bed,and a link 34 connecting the solenoidplunger with the end of the levertoward the exit end of the bed. Lever 32 bends outwardly toward theentry end of the bed, and a cam-shaped extension. 35 is pivoted to theinner face of the bent portion on an-axis perpendicular to the axis onwhich the lever itself pivots. A

spring 36 normally holds the extension 35 in a position overlying theedge of the bed, as shown in Figure 4. Where the front wall of a cartonengages the extension, the extension pivots out of the way to allow thecarton to pass, as shown in Figure 5. Thereafter the extension springsback under the back flap 17 of the carton. A limit switch 37 is mountedon the bed and is engaged by the carton as soon as the extension springsback. The limit switch closes to energize solenoid 33 while the cartonis passing, and thus swings lever 32 clockwise about its pivot. Theextension 35 lifts the back flap about its transverse fold line so thatfinger 19 can engage it. Immediately thereafter the finger depresses theback flap, as shown on carton C in Figure 1. Next the carton PatentedMar. 22, 1960 3 passes under plate 20, whichholdsbothtransverselyfolding flaps'down, as already explained.

From the foregoing description, it is seen that my invention aifords' asimple mechanism for automatically and positively, lifting transverselyfolding flaps of a carton to positions where conventional, closing.means on a sealing apparatus can engage these flaps. The mechanism hasfurther advantages that it can be installed on existing. apparatuswithout otherwise altering the structure, and it eliminates the effortand safety hazard of lifting the flaps manually.

While I have shown and described only a single embodiment of myinvention, it is apparent that other modifications may arise. Therefore,I do not wish to be limited to the disclosure set forth but only by thescope of the appended claims.

I claim:

I". In a sealing apparatus which includes a slider bed, means forpushing cartons along said bed, each carton having front and back coverflapswhich fold along lines transverse to the direction of travel alongthe bed and initially project at downward angles from the horizontal,and means'for closing the transversely folding flaps and holding theminclosed position, the combination there with of a mechanism for liftingthe transversely folding flaps of each carton to angles which projectupwardly from the horizontal comprising means mounted on said bed inadvance of said closing and holding means and actuated by each cartonfor lifting the front flap, and cooperating means mounted on said bed inadvance of said closing and holding means and actuated by each cartonfor thereafter lifting the back flap.

A combination as defined in claim 1 in which said means for lifting thefront flap includes upright plates mounted in horizontal alignment onopposite sides of said bed, said plates having slots which slopeupwardly toward the exit end of the bed, and a rod slidably mounted insaidslots and extending across said bed in spaced relation thereabove.

3, A combination as defined in claim 1 in which said meansfor liftingthe back flap includes a lever pivoted on a. horizontal axis withrespect to said bed, motivating means connected to said lever, a camextension pivoted to, said lever on an axis perpendicular to the axis onwhich the lever itself pivots, spring. means urging said extension to aposition overlying said bed, said extension being adapted to pivot outof the way while a carton 'is passing andreturn to its positionoverlying the sea in time to lift the back flap of the carton, and

actuating means for said motivating means operated by the carton whenthe extension returns.

4. In a sealing apparatus which includes a slider bed, means for pushingcartons along said, bed, each carton having front and back cover flapswhich fold along lines transverse to the direction of travel along thebed and initially project at downward angles from the horizontal,

and means for closing the transversely folding flaps and 1 holding themin closed position, the combination thereofa mechanism for lifting thetransversely folding. flaps'co'mprising a pair of upright plates mountedin hori-,

zontal alignment on opposite sides of said bed in adspect to said bed,motivating means connected to said lever, a cam extension pivoted tosaid lever on an axis perpendicular to the axis on which the leveritself pivots, spring means urging said extension to a. positionoverlying said bed, said extension being adapted to pivot out of the waywhile a carton is passing and return to its position overlying the bedin time to lift the back flap of the carton, and actuating means forsaid motivating means operated by the carton when the extension returns.

5. In a sealing apparatus which includes a slider bed, means for pushingcartons along said bed, each carton having. a front cover flap whichfolds along a line transverse to the direction of travel along the bedand initially projects at a downward angle from the horizontal, and

1 means for closing the front cover flap and holding it closed, thecombination therewith of a device for lifting the front flap of eachcarton before it reaches said closing and holding means, said devicecomprising a pair of upright plates mounted in horizontal alignment onopposite sides of said bed in advanceof said closing and holding means,said plates having slots which slope upwardly toward the exit end of thebed, and a rod slidably mounted in said slots and extending across saidbed in spaced relation thereabove and adapted to ride up the slots undera. front flap as the carton advances along the bed.

6. In a carton sealing apparatus which includes a slider bed, means forpushing cartons along said bed, each. carton having a back cover flapwhich folds along a line transverse to the direction of travel along thebed lever, a cam extension pivoted to said lever on an axisperpendicular to the axison which the lever itself pivots, spring meansurging said extension to a position overlying said bed, said extensionbeing adapted to pivot out of the way while a carton is passing andreturn to its position overlying the bed in time to lift the back flapof. the carton, and actuating means for said motivating means operatedby the carton when the extension returns.

References Cited in the file of this patent UNITED STATES PATENTS1,406,165 Beckmann Feb. 14, 1922 1,974,192 2,764,123 Derderian Sept. 25,1956 Paxton Sept. 18, 1934.

